// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == 'object' && typeof module == 'object')
    // CommonJS
    mod(require('../../lib/codemirror'));
  else if (typeof define == 'function' && define.amd)
    // AMD
    define(['../../lib/codemirror'], mod);
  // Plain browser env
  else mod(CodeMirror);
})(function(CodeMirror) {
  var Pos = CodeMirror.Pos;

  function forEach(arr, f) {
    for (var i = 0, e = arr.length; i < e; ++i) f(arr[i]);
  }

  function arrayContains(arr, item) {
    if (!Array.prototype.indexOf) {
      var i = arr.length;
      while (i--) {
        if (arr[i] === item) {
          return true;
        }
      }
      return false;
    }
    return arr.indexOf(item) != -1;
  }

  function scriptHint(editor, keywords, getToken, options) {
    // Find the token at the cursor
    var cur = editor.getCursor(),
      token = getToken(editor, cur);
    if (/\b(?:string|comment)\b/.test(token.type)) return;
    token.state = CodeMirror.innerMode(editor.getMode(), token.state).state;

    // If it's not a 'word-style' token, ignore the token.
    if (!/^[\w$_]*$/.test(token.string)) {
      token = {
        start: cur.ch,
        end: cur.ch,
        string: '',
        state: token.state,
        type: token.string == '.' ? 'property' : null,
      };
    } else if (token.end > cur.ch) {
      token.end = cur.ch;
      token.string = token.string.slice(0, cur.ch - token.start);
    }

    var tprop = token;
    // If it is a property, find out what it is a property of.
    while (tprop.type == 'property') {
      tprop = getToken(editor, Pos(cur.line, tprop.start));
      if (tprop.string != '.') return;
      tprop = getToken(editor, Pos(cur.line, tprop.start));
      if (!context) var context = [];
      context.push(tprop);
    }
    return {
      list: getCompletions(token, context, keywords, options),
      from: Pos(cur.line, token.start),
      to: Pos(cur.line, token.end),
    };
  }

  function javascriptHint(editor, options) {
    return scriptHint(
      editor,
      javascriptKeywords,
      function(e, cur) {
        return e.getTokenAt(cur);
      },
      options,
    );
  }
  CodeMirror.registerHelper('hint', 'javascript', javascriptHint);

  function getCoffeeScriptToken(editor, cur) {
    // This getToken, it is for coffeescript, imitates the behavior of
    // getTokenAt method in javascript.js, that is, returning "property"
    // type and treat "." as indepenent token.
    var token = editor.getTokenAt(cur);
    if (cur.ch == token.start + 1 && token.string.charAt(0) == '.') {
      token.end = token.start;
      token.string = '.';
      token.type = 'property';
    } else if (/^\.[\w$_]*$/.test(token.string)) {
      token.type = 'property';
      token.start++;
      token.string = token.string.replace(/\./, '');
    }
    return token;
  }

  function coffeescriptHint(editor, options) {
    return scriptHint(editor, coffeescriptKeywords, getCoffeeScriptToken, options);
  }
  CodeMirror.registerHelper('hint', 'coffeescript', coffeescriptHint);

  var stringProps = (
    'charAt charCodeAt indexOf lastIndexOf substring substr slice trim trimLeft trimRight ' +
    'toUpperCase toLowerCase split concat match replace search'
  ).split(' ');
  var arrayProps = (
    'length concat join splice push pop shift unshift slice reverse sort indexOf ' +
    'lastIndexOf every some filter forEach map reduce reduceRight '
  ).split(' ');
  var funcProps = 'prototype apply call bind'.split(' ');
  var javascriptKeywords = (
    'break case catch continue debugger default delete do else false finally for function ' +
    'if in instanceof new null return switch throw true try typeof var void while with'
  ).split(' ');
  var coffeescriptKeywords = (
    'and break catch class continue delete do else extends false finally for ' +
    'if in instanceof isnt new no not null of off on or return switch then throw true try typeof until void while with yes'
  ).split(' ');

  function forAllProps(obj, callback) {
    if (!Object.getOwnPropertyNames || !Object.getPrototypeOf) {
      for (var name in obj) callback(name);
    } else {
      for (var o = obj; o; o = Object.getPrototypeOf(o))
        Object.getOwnPropertyNames(o).forEach(callback);
    }
  }

  function getCompletions(token, context, keywords, options) {
    var found = [],
      start = token.string,
      global = (options && options.globalScope) || window;
    function maybeAdd(str) {
      if (str.lastIndexOf(start, 0) == 0 && !arrayContains(found, str)) found.push(str);
    }
    function gatherCompletions(obj) {
      if (typeof obj == 'string') forEach(stringProps, maybeAdd);
      else if (obj instanceof Array) forEach(arrayProps, maybeAdd);
      else if (obj instanceof Function) forEach(funcProps, maybeAdd);
      forAllProps(obj, maybeAdd);
    }

    if (context && context.length) {
      // If this is a property, see if it belongs to some object we can
      // find in the current environment.
      var obj = context.pop(),
        base;
      if (obj.type && obj.type.indexOf('variable') === 0) {
        if (options && options.additionalContext) base = options.additionalContext[obj.string];
        if (!options || options.useGlobalScope !== false) base = base || global[obj.string];
      } else if (obj.type == 'string') {
        base = '';
      } else if (obj.type == 'atom') {
        base = 1;
      } else if (obj.type == 'function') {
        if (
          global.jQuery != null &&
          (obj.string == '$' || obj.string == 'jQuery') &&
          typeof global.jQuery == 'function'
        )
          base = global.jQuery();
        else if (global._ != null && obj.string == '_' && typeof global._ == 'function')
          base = global._();
      }
      while (base != null && context.length) base = base[context.pop().string];
      if (base != null) gatherCompletions(base);
    } else {
      // If not, just look in the global object and any local scope
      // (reading into JS mode internals to get at the local and global variables)
      for (var v = token.state.localVars; v; v = v.next) maybeAdd(v.name);
      for (var v = token.state.globalVars; v; v = v.next) maybeAdd(v.name);
      if (!options || options.useGlobalScope !== false) gatherCompletions(global);
      forEach(keywords, maybeAdd);
    }
    return found;
  }
});
